1. Technical Field
The present invention relates to a vehicle occupant restraint system, and is particularly directed to a vehicle occupant restraint system including seat belt webbing for restraining a vehicle occupant.
2. Description of the Prior Art
Seat belt systems are commonly used to restrain vehicle occupants. A typical seat belt system for a vehicle occupant includes a length of belt webbing extensible about the vehicle occupant. The length of belt webbing extends across the occupant's torso to a webbing guide or D-ring located adjacent the occupant's shoulder. From the D-ring, the length of belt webbing extends downward to an anchor point located adjacent the vehicle floor. In the event of sudden vehicle deceleration such as occurs in a vehicle collision, the occupant initially continues to move forward relative to the vehicle, but thereafter is restrained by the belt webbing.
The vehicle occupant can experience a sudden load if the occupant's forward movement is restrained by an inextensible length of belt webbing. To alleviate this sudden load, it is known to include an energy management device in the seat belt system. When the occupant engages the belt webbing with sufficient force, the occupant's movement is restrained at a reduced rate over an increased period of time. This can reduce the abruptness of the load experienced by the vehicle occupant.
In some known seat belt systems, the D-ring is manually adjustable between different positions so that the D-ring and the portion of seat belt webbing extending across an occupant's torso may be located in positions selected by the vehicle occupant. Positions of the seat belt webbing other than the position selected by the vehicle occupant may, however, provide improved occupant restraint during a vehicle collision.